xref: /freebsd/lib/libc/string/wcstok.3 (revision fa9896e082a1046ff4fbc75fcba4d18d1f2efc19)

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.\" strtok_r, from Berkeley strtok
.\" Oct 13, 1998 by Wes Peters <wes@softweyr.com>
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.Dd October 3, 2002
.Dt WCSTOK 3
.Os
.Sh NAME
.Nm wcstok
.Nd split wide-character string into tokens
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In wchar.h
.Ft wchar_t *
.Fn wcstok "wchar_t * restrict str" "const wchar_t * restrict sep" "wchar_t ** restrict last"
.Sh DESCRIPTION
The
.Fn wcstok
function
is used to isolate sequential tokens in a null-terminated wide character
string,
.Fa str .
These tokens are separated in the string by at least one of the
characters in
.Fa sep .
The first time that
.Fn wcstok
is called,
.Fa str
should be specified; subsequent calls, wishing to obtain further tokens
from the same string, should pass a null pointer instead.
The separator string,
.Fa sep ,
must be supplied each time, and may change between calls.
The context pointer
.Fa last
must be provided on each call.
.Pp
The
.Fn wcstok
function is the wide character counterpart of the
.Fn strtok_r
function.
.Sh RETURN VALUES
The
.Fn wcstok
function
returns a pointer to the beginning of each subsequent token in the string,
after replacing the token itself with a null wide character (L'\e0').
When no more tokens remain, a null pointer is returned.
.Sh EXAMPLES
The following code fragment splits a wide character string on
.Tn ASCII
space, tab and newline characters and writes the tokens to
standard output:
.Bd -literal -offset indent
const wchar_t *seps = L" \et\en";
wchar_t *last, *tok, text[] = L" \enone\ettwo\et\etthree  \en";

for (tok = wcstok(text, seps, &last); tok != NULL;
    tok = wcstok(NULL, seps, &last))
	wprintf(L"%ls\en", tok);
.Ed
.Sh COMPATIBILITY
Some early implementations of
.Fn wcstok
omit the
context pointer argument,
.Fa last ,
and maintain state across calls in a static variable like
.Fn strtok
does.
.Sh SEE ALSO
.Xr strtok 3 ,
.Xr wcschr 3 ,
.Xr wcscspn 3 ,
.Xr wcspbrk 3 ,
.Xr wcsrchr 3 ,
.Xr wcsspn 3
.Sh STANDARDS
The
.Fn wcstok
function
conforms to
.St -isoC-99 .